For many reasons so-called bi-folding doors formed of fabricated metal have become popular for enclosing large openings, such as for closets and cabinets. Various fitting arrangements have been provided heretofore for supporting the doors in the opening and guiding them during their opening and closing movement. Some of the prior arrangements have been disadvantageous by reason of the difficulty in assembling the same in the initial door, or installing them, or by reason of lack of adjustment in the device when installed.